Boston Port Act

The Boston Port Act of 1774 was one of the Intolerable Acts, becoming law on 25 March 1774. King George III of Britain had the port of Boston closed in response to the 1773 Boston Tea Party, preventing the Sons of Liberty from injuring British commerce, and all ships were kept out of the harbor. Salem became the new seat of government in Massachusetts, while Marblehead became the main port; the Port Act led to the other twelve of the Thirteen Colonies sending aid to Massachusetts, uniting the colonies in opposition to the British and leading to the outbreak of the American Revolutionary War the next year.